Alot of us here on FT may have alot more than 200-300K total credit lines. Especially FTers that own businesses. We just don't brag about how much total credit lines we have. Just the rewards earned.

We get the cards for the large signup bonuses. Why not? ^

We have some cards that we've kept a long time (for us, a few old retail cards such as Sears, Penny's & Macy's and for me, a couple of old credit union non rewards cards) for credit history. We do use the retail cards when they offer us nice discounts for using their cards, otherwise we use the rewards based cards for our purchases.

There was a time we used our checkbook for buying everything. Now we use the cards and get rewarded. Of course, we always pay the statement balance every month so no interest charges. ^