Should reading and user groups be in work time?

Over the years, I've had a lot of discussions with clients over the timing of  my Vectorworks user groups. Some say the user group meetings should be after hours, so that it doesn't get in the way of work. Mainly it's the employers and self-employed that say this. 

The employees tend to say that if the user group is an advantage to the employer, then the user groups should be in work time. After all, if they get better at Vectorworks that is an advantage to the business. 

If you went to a seminar on improved insulation, solar water heating, or some other construction technology, would you expect that to be after hours? All the building seminars I've seen are in work time. the presenters don't want to work after hours, so why is it the that the expectation is that the user group meetings should occur after hours?

AS it's turned out, I run 4 different sessions times each month for my subscribers. They can choose a time during work, or in the evening. As it turns out, the most popular time is Friday morning...

I recently started reading a book to help my business. Should I be reading this during business hours. The common wisdom is that I shouldn't read this during business hours. If the book turned out to be a real bonus to my business, why not read the book during work time. 

It is alright for me, I'm self employed, so I only have myself to answer to. Image if you worked in a large company and you were sitting back reading a book when your boss walked past. Ouch, you'd probably get fired. But if you learned something that would help the business, it would be a good thing...

By the way, the book I am reading is The 4 Hour Work Week by Timothy Ferris. you can read more about here at the blog of Timothy Ferris