The simple answer Do they sell out? Because if they do, then it's not too much (and may even be too little). The slightly more complicated answer Pricing can b

The simple answer Do they sell out? Because if they do, then it's not too much (and may even be too little). The slightly more complicated answer Pricing can be used in a number of different ways - for example, it can force only a certain 'level' of people (experience, money, focus in an area) to attend. Picking (randomly) EuroPython from your list at 210€ - if you attend, you know you will be surrounded by other people who believe the event is worth at least 210€ to them, as opposed to people who may only have a passing interest in Python. Similarly, topics will be targeted at your level - if you've ever been to a 'free' course on a topic you know really well and found it full of noobs asking basic questions that don't help you, then you will understand the value that these levels have.