I don't think professionalism comes into it, ifaxu. Way back in the days of Long Hours Gratuity for weekend working there were always the greedy guys who would volunteer to work weekends like they were going out of fashion. More sensible people, like me, used to queue up to give them their extra work (and money!).
Management ALWAYS wins in ATC... always have done, do now, and always will do UNTIL the ATCOs say enough is enough..