The majority of people don't meet long term partners while drunk in pubs and clubs. Most people there are just looking for a one night stand, as you can see if you are there 10 minutes before closing time and everyone makes a mad dash for anyone of the opposite sex ( normally someone they wouldn't go near without a mix of desperation and beer goggles ! ).
I also find that girls don't really need to sit there waiting to be chatted up, if they are genuinely intersted in you they will often make the first move and come over and say hello.
Every girl I have gone out with has been through meeting them via mutual friends etc.. and getting to know them a bit first. Staggering up to a woman in a loud club and drunkenly shouting in her ear isn't the best way !