Still can't get over the hatred of groups from some here - yes, some are bad, but others are good. Even after a third or fourth child you might want to go to a group and meet parents of children the same age, not just parents of children the age of your first child.
We've had dads come to my group quite happily - sometimes on their own, sometimes with their partner. We have several grandparents who attend.
Some groups are run in halls that are freezing, others are in halls with heating that is poor, some in halls with superb heating systems where you roast in the heat. Perhaps the heating issue relates to some of these kinds of halls having antiquated systems that need thousands spending on them, and the £1 per week for toddler sessions doesn't cover the hire of the hall, let alone the hall committee mending the heating. Most toddler groups I know bend over backwards to keep their subs really low - £1 per family - but still have to pay their overheads; as do the halls that provide the large spaces and storage for the groups concerned.
Some will have grubby toys, some will have clean toys: our toys get cleaned every term, and wiped over in between if they get crumbs or dirt on them. If they are grubby, why not offer to take a carrier bag of toys home to deep-clean them? (Though don't nick off with all the Bob the Builder toys like someone did at my group.)
Someone said - "i could not fathom why grown women were required to stand and sing heartily whilst the kids had no interest in it."
Perhaps because it actually helps the children to learn the songs if the adults that care for them sing alongside the (volunteer) leaders who might themselves feel nervous about singing out loud in front of an audience of parents who can't be bothered to join in. That ten minutes is the only bit of the session where the parents/carers are asked to join in - they don't have to bring their child to craft, or sit and playdoh, or do puzzles etc - and it is jolly hard work when the adults are standing either staring watching the leaders sing on their own or chattering over the top of the singing. If the adults are interested and enthusiastic, the kids pick up on that and will join in. If the parent is busier putting on their coat and chatting for an extra ten minutes, the child might feel that singing isn't worth bothering with either.