in fantasyland, yes... in porn, yes... in sexual activities, maybe...
in real life, nope... for the single fact that your dick is hidden from view and even a bulge is questionable when it comes time to actually perform. there's just no real way to confirm a guy is packing. if you're truly curious, all you really have to do is go about your day and whenever you need to make any type of transaction, just add "is there a big dick bonus/discount?" and then you will know the truth. try it, whether you're ordering at the mcdonald's drive thru or starbucks; hell, ask while you're buying a car wash. trust me, you'll learn real fast how important and advantageous it is having a big dick in the real world.