A nice comfy pair of sandals will work for shore excursions or just shopping around town. Just make sure they are not brand new and not broken in. There is nothing worse than wearing a new pair of shoes/sandals that hurt, so just make sure they are comfortable.
For those kinds of days, just a very comfortable walking shoe, probibaly something you already have and that are broken in. If your feet are killing you, then what good is the excursion? Even if I buy something new for an occasion like this, I make sure to wear them before, so they do feel good.
We were in the Mediterranean last year for 2 weeks and did a tremendous amount of walking. (I did not gain one lb.!!!) I wore tennis shoes when I knew we were going to be walking on rocky surfaces, but most of the time I wore a good sandal I bought at Kohl's that had 4 strips of velcro closures across the top. I love them! Were not expensive. The best thing about them is being able to adjust the velcro at different places on your foot as our feel always swell when walking alot, especially in warmer weather!
I just returned from the Caribbean and wore the same shoes there.
The aqua shoes we bought were also great at the beach - snorkeling, etc.
The type of sandals I love and used a lot especially at our European port and cities tours where Four Way Sandals put out by Aerosoles. On sale for about $25-30 and they come in many colors, but black will work best. I have found them in JC Penny, Sears, and most good department stores like Macy's, Filene's etc. There are four wide straps that cross the front with a solid back. The soles are rubber and the innersole is padded. They are open for air circulation but the toe and heel are partially covered. They look nice in slacks, shorts or even a jumper. These are for women. I have bought them for my married daughter and my elderly mother who really like them a lot. Good Luck. They should be on the store shelves before your European cruise.
I swear by Teva Kinetic sandals. They're padded for comfort and can handle getting wet. I walked many, many miles in mine with not a sign of a blister. (They're available online, too. Just search for "Teva" and you'll come up with sites where you can see them and purchase.)
I totally agree with Tevas. They are the best! I remember about 5 years ago, going to Disney World with my co-workers and I had a pair of strapped flip flop-type sandals. I have never had such foot pain in my life!! I ended up buying a pair of Keds with Mickey on the side, but my feet were already ruined and then, of course, the new shoes made their own blisters.
I bought my Tevas several years ago (after the Disney trip) and I swear they still look new. They were $65, but you can find them on sale at times. I can get them wet, and they won't pick up an odor, since they are open, your feet don't sweat, and they are easily removable (I just generally hate wearing shoes--well, my feet seem claustrophobic in confining shoes). And, every time you put them on they get adjusted to the tightness that you want....depending on feet swelling, etc.
I would swear by them and recommend them. No, they are not the most attractive shoes in the world, but when someone with nice, pretty shoes is wincing from pain, they look longingly at my painless Tevas!!
Funny you should mention this topic, cause I have been looking myself. I finally found some Birkenstocks on sale which were a really good deal. I wanted to have a comfortable sandal which had a strap around the heel. Anyway, Birkenstocks are a tad cheaper than Eccos, and in the same ballpark.
My all-time favorite sandals for travel are made by Rockport, since they are comfortable, give good arch support, and generally aren't as expensive as Birkenstocks (which I also like). The best thing about Rockport is that off and on they have models which are comfortable enough to wear all day tracking up and down hilly cobbled streets, but still look nice enough to wear with a dress for dinner. Saves packing!
I sadly don't see anything quite like what I have on their website right now (the "Sarasota" looks like an uglier version of one pair, and the "Pruja" like a less comfortable version of the other), but they seem to change all their styles with great frequency, so it's worth taking a peek if you have a Rockport store near you.