I will not. Because bitcoin transaction takes some time to confirmed
That is entirely up to the seller, he can decide how much confirmations are necessary before processing your order. For something like dried fruit, I'd say
zero confirmations would suffice. Just the appearance of the tx in the network is enough (plus not seeing other pending transactions from the same address beyond its current balance). Successfully pulling off a double spend would effectively cost way more than some dried fruit.
and I do not want to spend too much on transaction fees to buy dried food. Maybe something else more in value...
YOU decide how much transaction fee you want to pay. Transactions with fees as low as 0.00001 BTC are processed pretty much instantly. And lower (or even free) also works fine, although that may take a few blocks before getting included.
And besides, got any idea how ridiculously expensive the current transaction fees are with paypal, credit cards, and wire transfers? They're like 1000x as expensive, compared to Bitcoin.