Dre., I've got to hand it to you THIS topic is actually debatable.
I won't comment much on the original point, b/c I think we need to let some of the PG's have in on it, I will however comment on the comment about bars...
From a purely business stance, "ladies night" is something that's done to attract, well attractive customers. Bars (in the US, mind you, granted this is a UK article) are typically meant to serve one of two purposes: 1.) a place for people to get drunk and be left the hell alone (dives) and 2.) social gathering places - mainly for courting purposes but also for casual meetings, friends, etc. It is in the best interest of any business to stimulate growth and in retail especially this is done with sales and bargains. So, in essence, there's no difference between having a ladies night at a bar, as there is in having k-mart offer all women's blouses 50% off. You won't find many men who squawk UNFAIR! at k-mart because -their- tops aren't 50% off that week. However this involves a dynamic which is hard to speak on, but really does underlay the whole thing - sexual orientation.
"WHAT?"
Yeah...
See, to a gay man, it might be a crime that silk shirts aren't discounted when women's clothing is.
To a gay man, it might be a crime that a bar offers dollar draws on Tuesday nights to women and yet there's no such night for men.
And, I suppose in some strange reversal, it's a crime to a straight man that he can't work out in the gym while salivating over some hottie on the tread mill.
So in essence the issues brought up by this article and arguments surrounding it, are really talking less about sexism and more about heteronormativity. With this in mind, we can see why there's an issue with the UK man and his not getting a "fair" deal out of the gym. My response to such people is to simply join a different gym (unless there isn't another one to join, which means, tough **** deal with it). It's not as if there aren't men who would prefer to work out in a gym that wasn't exclusively all out-of-shape-men. There's even a chain of gyms in the US that promotes an atmosphere of non-jocky-ness, because they realize that most people aren't trying to be body builders, they just want to be in shape, and it's tough to feel comfortable when you're a lard ass sweating beads on the exercise bike and joe-muscle head is over there doing 30 reps @ 300 pounds, surrounded by his spotters and beefy friends who all leer in your general direction and snicker because of what a spectacle you must look like.
Obviously these are generalizations, and yeah, typically you'd eschew them, but it's worthwhile to mention b/c not every man and not every woman that goes into a gym, or a bar, is interested in being the object of attention - and in this case, I'd say it's more important to identify these trends because of the fact that they're rooted in heteronormativity and today's progressives are challenging these with ferocity (which is a good thing - most of the time.)
Meanwhile HERE you can totally find bars that offer a men's night out, not that I'd go, cause it's mostly gay men and I'm not gay.
HERE you can find gyms that offer a more comfortable atmosphere for your workout where you're not scrutinized by block heads.