Nope. You can buy any GSM android phone but if it's not t-mobile branded, you'll have to unlock or get an unlocked phone to use it with t-mobiles plan.Are there any obstacles to buying an Optimus without a data plan?
Without? You can do anything anyone else can except freely use the cell network for calls and data. Smartphone on wifi with no cell plan at all is what I have my brother who's still in highschool on. No monthly fee, all the features of a regular cell plan, just without the range :PIs this a reasonable idea for someone who only wants a phone without all the social media bells & whistles?
Would it require rooting? How and why?
Oh and to answer your question, rooting has nothing to do with any of this :P It's just nice to have