If I accept a lower pay job, I'm doing my part on lowering the pay for that job in the collective bargaining between employer/employee. You might think it's not detrimental for you, but it's detrimental for everyone who competes for that job. And, as your argument is truthful, it will become a spiral: no disincentive in accepting the $2/hr job, then no disincentive in the $1.95/hr job, then ... for n iterations until there's no disincentive in doing it for free, for the experience or the kicks.
And, of course, in the end the benefit will go the usual beneficiaries.