Brokers response to due diligence requests

The last 8 months, I've brought 3 deals under LOI and 2 out of 3 brokers act as if I'm asking a huge amount of questions in the due dil phase. I gave one of them a list of documents and questions which was about 1.5 pages long. Total was about 20 document requests and about 20 questions. He said he had "never seen a list this long in 20 years".

Are they acting this way so as to prevent me from asking more? Everyone I've spoken with said they request a lot more than I have and it's just a game brokers play.