Of course, men are not subject to the same sexual standards as women. It is accepted that they can sow-their-wild-oats all over the place (including with married women - or even men), and appear, suited and booted at the alter in clothing that doesn't give their game away.
It's archaic.
But - if you choose to marry into the RF, you either accept the tradition(s) or flout them. And, if you flout them, you can't pick and choose which suit and which don't. If you want the privileges and benefits you have to abide with the rules. However, these will change over time but if you are one of the 'modernisers', you are going to get some flack. Not everyone is happy with Charles' modernising of the RF, nor his passion for environmental matters - and he's been criticised for his 'taste' in architecture. Considering his background, I feel a sneaking admiration for him.