To be honest, this change of the TOS is the next step to make the hole Second life more and more uncomfy for a lot of users, so also for a lot of customers from merchants.
Why? Thats quite easy.
In the US, may be the people are used to give there payment accounts like Credit Card number, paypal or.... on request in the internet. I don´t know. I just know, that in Europ, it realy needs some more trustment that someone will give this kind of infos to a company from the US.
So what will happen? a lot of NEwcomers to SL will get frustrated soon, when they see, that they have no other way than to give lindens there bank account infos.... ohh i forgot, they even don´t accept it for Europeans, as they just accept credit card, or paypal.
This means that most of there users are just able to get money in SL, if they trust Lindens, an american Comany, were most European will not trust on the first moment.
And you can discuss about Laws and so on, what might be the reason why they had do decide this way, sorry, thats nonsens, as they run this game, and so the give the rules.
The only real reason i could see for this change in there TOS is just, that they are yealous on the money the 3rd party companies earn with there policy. But to be honest, i think that all the 3rd party companis who cared till now for the money exchanges still earned there money, cause of the services you get, the change rate and so on.
And now, Linden is able to set up an exchange rate, that everyone has to accept, as they have the monopol than, with the exchange rate. But im sure, that this is one of the next steps to get rid of a lot of useres. And when you think about all the decisions they made during the last years, i realy more and more get the impression, that there goal is realy to get rid of most of the useres