How would they be able to take Bitcoin from the people when they don't even provide Bitcoin addresses to their users? Paypal users are not allowed to make Bitcoin deposits to their accounts.
Your worries would have some ground if Paypal would allow users to make Bitcoin deposits to their Paypal wallets but not withdrawals, and would purely settle in fiat all Bitcoin-denominated transactions with partner merchants. For now, it seems there is no actual Bitcoin involved but mere IOUs.
I agree with you even we have to consider the latest paypal bitcoin integration buzz also one of the reason to push market ( out of several reason) . Personally if i want to use paypal for bitcoin transaction the reason should be cash out to fiat currency for my regular need . Other wise i wont transfer to paypal all my holdings