That's a good point. For the past 10 years or so, Scheduler has always given users the option to choose between individual bookings and group bookings in this screen. However, we don't use this feature in our own installation, so I'm not sure what is actually required by users.
I'd be interested to hear how people are using this feature and what changes they would like in future versions.
At the moment, the "book for myself" option cannot be hidden, or the order of the menu changed.
Of course, as a workaround, you could change the code - if you feel competent to do so -; the menu is assembled in student.php near line 75 (comment "Print group selection menu if given.")