Why 300$ to get 100$ into it?
Intermediaries, unless you were in US or Japan, you probably had to go through a several scammy/scummy different services like liberty reserve, and $10 or so, 5% or so each hop you'd not end up with much at end. Depending on timing it might not have been a wise decision to deal with Gox even when apparently functioning though.
If you bought 100$ worth of bitcoins back then you would have been very tempted to sell after a x10 or x100
Also very true.