If I put zero fee, is it possible that my transactions will be confirmed anyway?
that is also a possibility but it is a race, when there are 70,000 transactions which at least (with a big optimistic view) 50,000 one of them have high fees such as 0.0003
BTC fees per byte, nobody will mine your zero fee transaction.
Odds are a Zero Fee transaction will be ignored.
(and it will do nothing but lock up the transaction for ~72 hours before it is released back to you.)https://www.cryptocoinsnews.com/death-zero-fee-bitcoin-transaction/Zero-fee transactions were the norm in 2011, the exception in 2012, increasingly rare since, and now finally gone.
For a long time in Bitcoins existence, miners would process transactions without fees.
All miners today expect transactions to include fees due to the overall volume of the network and to avoid spamming of the Bitcoin network.
