You are an average college student, can you say that your financials, experience, wealth is equivalent of someone that is double your age? These older men have already obtain their careers by this age, have been with multiple women, and have already established their financials to enjoy themselves.
Some providers do discriminate on a clients age, some will not see anyone under 30, and some will not see anyone under 40. I'm not in my early 20's anymore, and I can tell you, when your at my age, you view a 20 year old as just a child. To answer your question, yes, some providers will discriminate on a hobbyist age. Some do prefer mature men because they have already obtain everything, and only want to enjoy.
As it relates to occupation. Yes, some do. You are in college, and are a college student. Do you think that your finances are equivalent to someone that has a successful career and has been working for over 30 years to save for his retirement, have good money in his bank account, and owns property such as a house or several cars?
Some providers want a stable client, someone that they know are able to support them financially. Sure, you may save a few hundred dollars to see a provider, but, guys with good professions can see that same provider like 4 or 5 times a month without it hindering his finances. Some providers do invest in certain clients because they are stable in their financials.
I am sure there are some that disagree with me. Some will say that they don't discriminate on age and profession, and as long as he is a nice guy and are able to afford their services, then it should be okay. Well, if you over 30, and have a good profession, your more than likely to be successful at influencing her decision to see you. That, along with provider references of course. Have fun!