The Oasis is a really nice RV park and although you can't walk to the casino it sits right off Las Vegas blvd and it's a short easy drive to the strip. What we do is drive the car to Luxor, park the car, and then do a combo of walking and using the monorail system which takes you around the strip-both sides. It stops at several casino's and you can get off and on as often as you want if you purchase appropriate ticket (very reasonable price) the Oasis has a really nice cafe and a great outdoor swim area. After staying there it's the only place we stay. Make sure to check out Hoover Dam while you're there. Not much water in Lake Mead but the dam is a must see as is the new arch bridge that spans the Colorado River. It's the second highest bridge in the United States. It's quite amazing to see them both.
We have never used it but I think the Oasis may have a shuttle to the Strip. Now that I think about it I'm not sure there is a shuttle but honestly it's so close to the Strip and a very easy drive. If you needed to rent a car there are rental services close by as well.