Only a little bit closer Plym, but I guess I do have the privilege of spending more time 'behind the scenes' than the majority of fans. That said, I don't pretend to know the details of JBs financial transactions with the club other than what I researched in the publicly available club accounts. My understanding is that they are as you say loans, but am not convinced that is particularly unusual.
To my mind all football club owners fall into one of four categories:-.
1. The truly altruistic-i.e those fans who somehow end up with enough loot to pump into their favorite club and don't care if they loose it all and will 'happily' walk away without recouping their investment (the Bristows at Torquay are a good example).
2. Very wealthy businessmen who buy football clubs as status symbols (Chelsea)- they have so much money that it doesn't really matter if the club makes a profit or not and they may or may not end up becoming genuine 'fans'.
3. Hard nosed businessmen who will invest in a club and if success doesn't come who cut their losses and run, whatever the consequences for the club. (perhaps the new world consortium).
4. Businessmen who can see an investment opportunity and are wiling to risk a certain amount of money, providing they have a reasonable chance of recouping their investment - hopefully making a profit in the process. I see JB as very much in this category-he certainly doesn't appear to have loads of money to waste and will want to get his money back, but equally if the club can be self sustaining-i.e income equals outgoings or better, he believes there is a real opportunity to make some money AND have a successful football club. Contrary to some opinions I don't see how success on the pitch and an owner making money should upset some people - they should certainly not be mutually exclusive.
The bottom line is that JB was a reluctant investor who like many has now become a real fan. Whether he can afford/wants to continue to prop up the club and lose money remains to be seen, but as it stands the club is (apparently) almost now self sustaining so it would be natural to want to recoup some of his investment. The precarious nature of football means that it is a high risk business and over investment is no guarantee of success hence the prudent approach.
A long winded answer to a short question but why any investor recouping their investment (with interest) would upset anyone I have no idea.