I've actually experienced this in different degrees depending on what I was wearing etc. When I first started riding my Navigator, I didn't have the cycling clothes, I wore shorts and tanks/t's whatever I could find that fit. Very few would make eye contact with me.
After I made my own bike gear, the first time I was on a ride, I got a different reaction from riders. Many would smile or at least return a wave or eye contact. When I have stopped to HELP people in street clothes on "beaters" in my full gear, I get GLARES from road bikes and others just because I've stopped to help someone who wasn't dressed "right" or on the "right" kind of bike etc. This has happened more than once so I know it was/is a trend.
I've had minor problems and pulled over and few would even ask if I was ok, most of the time it was walkers etc.
Fast forward to me taking a Trek Pilot 1.2 onto the MONON for a test ride on the MONON, nearly EVERY rider that I waved to/spoke to etc reciprocated. I kicked the chain off while trying to shift gears and the chain was in a strange position, since it wasn't my bike, I was trying to be VERY careful not to scratch it. Several riders did pass me, but I did have a guy on a road bike stop to help me put the chain back on correctly.
I know from experience that partly due to the fact road bikes are MUCH faster than I am, I'm going to be riding solo. Some are at least friendly on club rides (now that I've been coming for a year regardless of my NOT being on a road bike) but there are still some that have laughed in my face for not being on a road bike.
I treat people the way I'd like to be treated or have someone in my family treated if they were on the trails/roads etc. I have no control over how others were raised or choose to behave.