Yesterday I visited a store and tried one out. I decided it is simply too heavy and too large for me and car.
The salesman was very helpful, showing me how to adjust my Rollator and giving me good advice: don't push with your arms, use your legs to move it.
So I will try putting those two rules in effect, and when it comes time for a nicer Rollator, that is the store that will get my business. This time I will try to make some kind of cover to keep the airlines from moidalizing it.