Well, I adore training, and I adore sparring - and I would give my eye teeth for a fight, even at the most baby level. But there's precious little chance of me getting even an entry-level inter-club tournament bout. It's one of the reasons I've joined kickboxing classes, because at least tournaments for KB do exist in the UK for women.
I know what you mean though, about 'why' spar if you're not going to get a fight (either because one doesn't want to, or due to other factors such as lack of opportunity, age, weight, whatever). At least by training and sparring you stand a better chance if you get into an unpleasant situation in 'real life' (such as being grabbed by a person with wicked intentions, or in an attempted robbery, or something). I'd say training in any martial art has got to be a good idea for that alone. MT has not only improved my mental awareness, but also improved how I stand and walk, as well as toning my body generally.
I think women in particular can gain a lot from training and sparring because generally speaking a lot of women are not very physical - they might run, or do pilates, but don't often push themselves physically and mentally the way you do when sparring. That's got to be a good thing; to have physical power. I'm not finding this easy to explain - but the closest I think I can get is the feeling I got the first time I shot an arrow - all that power and force as the arrow shot across and hit the target, and that power came from ME. Yes, obvs the construction of the bow gave me maximum force for my pull, but it was still MY physical muscles that provided the initial energy. It was an amazing buzz. And the realisation of Wow, yes, I'm female, so I'm not going to be as strong as a male, but I CAN do this, I do have physical strength.
I am Woman, hear me Roar!
Besides which, there's no better feeling than landing a really good punch or kick onto a worthy opponent, is there!!!