This is a tricky one. When lead generation companies tell you that no incentives were offered for the leads you are about to buy, they are telling you that the leads did not receive any incentive (like a free iPad) to fill out a survey. Maybe yes. Maybe no.
The tricky thing is, most lead generation companies just do not mention this point at all, which could well mean you are being sold leads that thought they may win a trip to Hawaii, a free laptop or whatever other incentive lead chasers choose to use. Think those have a chance of converting? Not so much.
This is actually a question you need to ask any lead generation company you are considering as your lead provider. It is important to know how they work. What are their ethics? Where do they get their leads? How fresh are they really? What do they do if you get leads filled out by the family hamster? And so forth. Never assume something about a lead generation company until you have checked it out. Ask questions over and over if you do not feel you are getting straight answers.
A lead generation company is a partner in your success. If that partner short-changes you on leads, you received the short end of the stick. Check around until you find a company that genuinely wants to and actually does work with you. It is your career and your business. You are in it to succeed and the minute someone does not help you with that goal, you need to move on.