Not sure I would call the Premium Bonds reckless, at least compared to other forms of gambling.
It used to be a regular suggestion on investment programmes, as long as you put in a big enough chunk that you got at least close to the return on regular NS&I savings accounts, as it gave the investment a monthly entertainment aspect, and was part of a wider portfolio.
The smaller the amount, the more hit & miss it gets, as I seem to have found out: when I was maxed out, I got something virtually every month, though nothing big. Now it's 1/2 or 1/3 that I get a trivial amount.