Occasionally, an ungrammatical expression is very useful for making a point succinctly.
S.M. Stirling’s Conquistador has an example of this. (Conquistador is set in our world and an alternative world discovered in 1946 by an ex-soldier. An excellent read and reread. Published by Penguin, ISBN: 0-451-45933-4. Copyright © Steven M. Stirling, 2003.)
On page 296:
“Not bad,” Tom said, putting his mug down. “Well hopped, and a nice sharp taste … some local microbrewery?’
“We brew it ourselves,” Ralph said.
“I brew it ourselves,” Henry said, and offered his hand.
The issue: “I brew it ourselves” is ungrammatical, but it very efficiently makes the point, “We brew it ourselves, and I am the one who does the brewing.”