I love Vegas, and I really don't gamble very much at all.....maybe $20 or so in the slot machines, and that's about it.
You can go to the old downtown, that's fun to walk through, and they have that video show with music, on that overhead screen, nightly, I think.
Once when we went there, we signed-up for a river rafting trip. It wasn't one of those wild rafting trips, it was very smooth and no white rapids or anything like that. It started at the base of Hoover damn. I think it lasted about 4 hours. There were about 20 people, and everyone gets on one large raft. We met at a specified location that morning, (I can't remember which hotel), and then they take you on a bus to where the trip begins. By the time you take the bus there, do the rafting down the river, and then get back to Vegas, it's pretty much the whole day.
There are also many comedy shows you can go to. Donny & Marie have a show. And there are many other shows you can go to with popular entertainers.
And then there's the food. Some great food to be eaten out there!!
There certainly isn't a lack of things to do.