It isn't 'buts': it's 'puts'.
Chris says: "I'm guessing it is a bit of dialect. I googled the song and it seems the band are from the Manchester area, so perhaps someone from there might know it." Well, I am from Manchester, and I can confirm it isn't dialect. I've listened to a recording of this song (which is in standard English) and I'm sure that the word is 'puts', not 'buts'.
So why does it sound like 'buts'? This is my theory:
In mainstream English pronunciation, the word 'put' and 'but' have different vowel sounds:
'Put' is pronounced /pʊt/. It has the same sound as in 'look' and 'could'.
'But' is pronounced /bʌt/. It has the same sound as 'cup' , 'run' and 'love'.
However, in most regional accents from the north of England, including Manchester, there is no /ʌ/ sound. Walk down any street in Manchester, and you will hear people say 'cup' 'run' and 'love' as /kʊp/ /rʊn/ and /lʊv/.
Now, here's the thing: when people want to minimise their regional accent, they often over-correct. A middle-class person from Manchester is keenly aware of the fact that the /ʊ/ vowel is associated with the local pronunciation, and will often make a great effort not to produce this sound. This often means that they'll avoid it even in words where it's meant to be, such as in words like 'put': it is not uncommon to meet Mancunians who are so keen not to sound 'northern' that they rhyme 'put' with 'cut' ( rather than with 'foot').
This is what we have in this song: a Mancunian singing in a more or less standard English accent, but with slight traces of his Manchester roots. One trace is a slightly odd 'u' sound, which is closer to an /ʌ/ than an /ʊ/. This is why 'puts' sounds like 'buts'.