Nope, I didn't clean out my lines first use either. Just pump some StarSan through, I use the hand pump 2 quart one, then tap up the keg, pour out 1/3 to 1/2 a glass, dump, then pour yourself a pint and drink. After the keg is empty however it's best practice to clean with BLC then rinse with water. I use the hand pump for that too. Saves CO2. Nowadays though I just push the 5 gallons of StarSan out of the keg using a lower psi like 5psi which sanitizes the keg, the disconnects, the lines, and the faucet while also purging all O2 and leaving CO2 in the keg to help against possible oxidation when filling. Works great.
Rev.