Not everyone follows all the recommendations, there are calculated risks. It is best to charge your batteries at the same ambient temperature that they will be used. For example, if you charge them inside with A/C around 72°F, then take them outside on a hot summer day above 100°F then a drastic increase in heat will cause the voltage to go up and you risk damaging your cells. I knew of a guy who bought a bunch of brand new packs, charged them up at home, put them in the trunk of his car and drove about an hour to the beach, but discovered that every single pack has swelled up in transit... they were all damaged beyond safe use.

Many indoor clubs allow charging inside the pit room, some require LiPo bags but many don't. The club in my area doesn't have any restrictions and about once or twice a year I will see someone's pack go up in flames inside the pit room which leaves a nasty chemical cloud and smell that remains for days. Sometimes someone can catch it early and grab the pack by the wires to get it outside before flames erupt, normally smoke billows for about 10-15 seconds first, but if you move too slow your best bet is to kick the pack while it's a burst of flame until it's outside. Every case that I saw where a pack caught on fire was due to abuse, either the pack was severely ballooned and eventually punctured or they over charged their pack by accidentally leaving their charger in NiMh mode.

There was one guy I know of who stored his packs in his hot garage in the summer and one of the packs had spontaneously combusted which set off a chain reaction to the other packs which burned down his garage... total loss of the garage and all its contents

Always discharge your packs to storage mode when not in use and minimize the time they are fully charged, heat is your worst enemy... as soon as the packs start to swell/balloon, then it's time to discard them!