Even just the salaried hourly rate of the people that work at the company that attend a 2 day workshop is already likely to be more than your megacorp rate. It doesn't matter to them, it's a rounding error to their initiative.

Before the economy tanked the last time I was at a couple of places that still sent people to conventions. I took a notebook and went to a mix of talks about stuff I was interested in and stuff my company was interested in. I don’t think there has ever been a conference that cost more to send devs to than what we cost the company for a day, so having us out of the office is the most expensive part of the deal (maybe that’s why some conferences go into the weekend).

I usually came back with enough notes to save me at least a couple of weeks of work. If you know how to listen, talking to an SME can save you a ton of time.

And from what I understand Microsoft is good at planning interviews to sound like they’re extemporaneous while they’ve actually worked out ahead of time what questions they need to ask you to get what they want.