The 25-year-old stressed that he is "not actually connected" to Syco after admitting that he fears viewers "will start turning" on him.
"I'm not actually connected with One Direction at all," he told Digital Spy. "I never met Simon Cowell before any of the auditions.
"But I can completely see why people think, 'Oh, hang on, One Direction are with Syco, Syco do Britain's Got Talent, they must be paying him!' Not at all. It's just if someone wants a song, I'm going to give it to them, especially if they're One Direction."
On a potential backlash from BGT fans, he added: "It's definitely something that I've thought about. It's an uneasy feeling [knowing] if it takes off and becomes a force that people will start turning on me."
Drewett also wrote The Wanted's debut single 'All Time Low' for himself, but ended up actively campaigning for the song to be given away.
"'All Time Low' was supposed to be for me, but the label at the time didn't really have much love for it," he explained. "So I was like, 'Let's be clever, let's get it out there, let's give it to where the love is', which was The Wanted.
"It was like, 'Let's be sensible about this, let's try and get some good out of this'. 'All Time Low' is a very important song because if that hadn't happened, I would have been another dropped artist. I'd be back on a building site."
Although he insisted that he doesn't feel resentful about the success other people have had with his songs, Drewett did confess to getting "very angry and frustrated" as his career stalled.
"Don't get me wrong, there have been times where I've been very angry and frustrated with the industry and with labels," he said. "But the bottom line is if you believe enough in the music, there should be no reason as to why you'd stop."