I guess everyone has a different definition of rip off. If someone took something from me I would be ripped off. If I ask to buy something from someone and I dont like their price and I refuse it, they have not taken anything from me.
If I dont like it I can open my own business and try to offer people the lowest prices possible or I could tell as many people as I want that I dont like the way he does business and I might even share with them the name of another dealer just as close as him and has it for much less.
If you did buy it and it was guaranteed for a year and it dies in less than a year and he refuse to replace it that's a rip off. If he gladly replaced it then he did you right.
I gasp at the prices at local businesses too but I have to believe they are also paying a lot in taxes and other overhead. When I gasp it's not actually gasping at the price of an rv part or a bag of apples or oranges, it's gasping at the printing of dollars that dilute the value of all the other dollars in the pool.
Just because you or I are able to do it ourselves doesn't mean everyone or even most people can do it. Most people CANT do it. Then you have the people who have no business touching those parts walk back in with a greasy new gear and want to return because they goofed the whole thing up. They would come way complaining that hes a rip off because he wouldn't return it and all he would have got is bad mouthing and a little profit off $35.00 I can see it more his way. Did you ever have a paper route or mow lawns as a kid?