I can understand new shoppers seeing a lot of complaints on the forum, and getting discouraged. How often do we enumerate our successful shops?
jk-- every company has guidelines on their site as to what they expect of their shoppers. Some describe it better than others, but none of them leave you completely in the dark. You can also usually look at a blank report before you shop to see what you must do. The great majority of rejected shops are for shoppers who didn't follow instructions. What makes you think you can't follow directions and guidelines? What other jobs have you worked at?
The money involved is usually to buy some product in the store. If you're going to judge customer service in a donut or a coffee shop, you have to buy food there, but you get reimbursed. Most of it makes perfect sense, but most common shops don't require large outlays for the product, and some none at all. There are also perks like reimbursed fast food, free groceries, reimbursed meals at restaurants, because you're playing the role of the customer.
If you hang on and ask questions, we'll help you.