Players on the 60 day DL do acquire service time.
Players on the minor league DL cannot be placed on the 60 day DL.
Not sure about salary, but I assume a player making league minimum placed on the 60 day DL would continue to receive it given that they continue to accrue service time.
Yes. I understand all this. But Chargois was optioned out in ST because he pitched poorly. It was basically right after that that he went on the shelf. The logical and undeniable conclusion is that he pitched poorly because he was hurt. At that time, the Twins could have rescinded his option (and thus saved an option for possible use in the future) and placed him on the MLB DL. The Twins decided not to do this. Other teams have. I can't think of examples, but this issue was discussed in May and examples were given then. The Twins decided that saving a few bucks and not giving Chargois service time was more valuable than saving an option and eventually a 40 man roster spot. The Twins didn't know that in March, but they did by May.
Just remember this some day in the future if the Twins want to send Chargois down but can't because he's out of options.