open days and assements are for a large part marketing and revenue generating.
Assements are a good thing in my opinion but how you steer that for a customer who wants to spend mutliple 10's of thousands I have always had my doudts especially when times are tough.
Again open days and assements are to make the punter feel special and that they have something different compared to the rest. Thus making them more willing to pay for what they think is a premium product.
Most mod schools don't need to bother as there advertising is done by word of mouth and if they are training at capacity or a bit below they don't need to.
Bigger schools have huge overheads and they need a steady through put otherwise they quite quickly get into trouble with cash flow as cabair have proved. They need folk to sign up and pay cash months in advance of starting otherwise the trouble starts getting the current students through.
In some ways is quite like a pyramid selling scheme where by the current students are really desperate that new punters turn up because the money from the new punters is paying for the fuel etc to allow them to get the training done.