You can import the same seed in as many wallets as you want... Your wallet in itself does not contain any bitcoin(s), it only contains the master private key from which other private keys can be derived. Derived keys can be used to sign transactions spending your funds.

For example, if you have a wallet managing 1 private key, and the address belonging to this private key has one unspent output with a value of 1 BTC, you can import the seed for this wallet into 50 other wallets. Each wallet will show a balance of 1 BTC.
If you spend this unspent output of 1 BTC in any of those 51 wallets, the balance of each wallet created by importing the same seed will be 0.