Lookout for the guy,is he comes to that place often or he linked with the players?
Most probably it will be just to gamblers if he lost his money from these kind of bets so he actually looking for everyone to lose.
It is indeed suspicious, but if we have money that can be spent it does not hurt to try it because this is gambling and maybe it will be another lucky factor that might make us win easily.
Its our money,why we want someone else to decide what we need to do,we know that results in gambling can be never predicted so how can we trust a random person with our money.
It's not that we are going to let someone to decide what we should do, it is all about having doubts because of random informations that a random stranger could tell you, and it is not also like we are entrusting to them our money by listening to what they spread. The problem here is our minds, we are just being extra careful not to lose our bets making us to hesitate, one wrong move and you're done.