Do you wave thanks when others let you merge in front of them?

Why would I want to wave (as if to give my approval) to some bozo who did not merge earlier. When people cut into a line in front of others--others who had properly merged earlier--the result is that everybody further back in the line ends up being pushed back further.

That results in those who had planned ahead and merged properly being further delayed.

The individual to whom so many would wave is therefore rewarded for bad actions.

Try to access the I-5 north-bound express lanes from south of Seattle in the afternoon. You will find many "late mergers" waiting until the last minute to merge (in many cases illegally) which ties up traffic both in the merged lane and the travel lane to its right being delayed.

Were I to wave to such persons my middle fingers would be constantly raised in their direction.

Bad behavior should not be rewarded.

@AlForget
The poll question is, "...when others let you merge..." and not, "...when you let others merge..." When others let me into traffic instead of cutting me off because someone else ahead of me was a bozo (and, for the record, I try not to be that guy), I appreciate their consideration and wave to show that I noticed their behavior.

First, it must be understood that letting another driver merge into traffic is not a favor - it's basic defensive driving, and in some circumstances a legal requirement. A wave of thanks should therefore not be expected or be a cause for taking offense if it doesn't happen.

That said, I do wave or smile if I happen to make eye contact because doing so makes the world a slightly friendlier place.

PeopleCan'tDrive makes a great comment: it is both utilitarian, and it has some spirit / zest. I concur! Now what about those drivers to the right at a simultaneous approach uncontrolled intersection, who in an overabundance of courtesy, demand with a stiff wave and air of impatience, that the driver to the left proceed first? Truly Seattle, I say! After refusing to accept the improper favor too many times, I now take a deep breath, give a smile and nod / wave, and proceed first through the intersection.

Allowing other drivers to merge in front of you is not only defensive driving, it shows a higher intelligence - it prevents slow downs. It shows knowledge that the person trying to merge won't just evaporate, they are there whether you like it or not, right or wrong. It shows the realization that it is not possible to have perfect timing every time we merge into traffic; and if people are not allowed to get on into traffic, they will stop, then everyone stops. At that point it becomes irrelevant who "owned the road" ; traffic still backs up. And still, the attitude seems to be "look out for myself and to heck with the people behind me as long as I can justify my actions by law". Even though the lights on the on-ramps act to reduce the odds of this type of thing happening, how many seconds will it actually delay a person to let several people on in front of you? And, then there is just plain courtesy and concern for another person - yes I give a thank-you wave; because that person who let me on is obviously of superior intellect and is willing to share it with others.

Yes, always, and it makes me crazy when others don't. I want to take back my allowing them in!

Oh, I must have missed the part of the question that mentioned anything at all about a freeway!!! Apparently nobody posting here ever drives surface roads where it is quite common to let a car pass in front when entering from the side just before a traffic light. You know, where traffic is already stopped and waiting for the light?