For your survey you should group people according to the amount of time they spend on the road with their RV and whether they boondock - camp at primative campsites.
We travel and stay at any given campsite for 1-2 nights on average. If one campground does not have showers and another one we will be at within the next couple of days has showers we will wait to use the showers at this location.
When a larger than average RV shower is important it will shape the decision as to which type and how large an RV is purchased. Trailers have more space for showers than slide-in campers or Class B or C motorhomes.
There are a number of factors in terms of whether an RV has a "wet" or "dry" bath with the latter having a dedicated shower area. Even so we have friends that have dry baths and never use the showers, only the ones at the campgrounds and RV parks where they prefer to stay for this reason in particular.
As a student your professor evidently has not taught you how to do proper research and survey techniques. First you need to understand the general aspects of a situation and then do the survey to provide a means for analysis. You have done this backwards. I would spend time at local RV parks and different type of campgrounds (in terms of amenities provided) and as them about showers. Take their feedback and then and only then create a survey.