Luton is a very weak team. the team that was just promoted to the premier league this season is currently still in the relegation zone in the English league standings table. and before away against liverpool at anfield Luton played at home and lost even at home against a team that was both a promotion team and both in the relegation zone shefield united also lost. so liverpool won by a landslide, it's a normal thing even though they couldn't play with the full effect of several injured players.
Luton isn't a very strong team but they also don't their selves to loose just like that, especially at home they always make sure they are able to secure a goal before the end of the game which has been observed in few if their games recently even in the game they lost at home they had a goal and now against Liverpool the were able to still get a goal but then the superiority of Liverpool was displayed over them before the end of the match. Liverpool was definitely going to win despite the fact that Luton had the first goal, it wasn't a guarantee they were going to win.
Liverpool hasd a very brilliant play and they won getting extra three points at the too of the table isn't a bad one after all and they have further kept Arsenal some good points away from the top of the table but Manchester city is gradually closing in.