If they are all different (i.e. you choose your numbers and make them different) then yes you’ll increase your odds. Same for a raffle, except you don’t need to worry about the numbers as each ticket is unique. But if everyone buys more raffle tickets with the same multiple, then your odds don’t change. If everyone buys more lotto tickets, everyone’s chances of winning increase (but also the odds of having to share the jackpot).