The Israeli-owned EcoStream shop in Brighton has closed in the wake of weekly boycott protests.
EcoStream, which sold SodaStream recyclable bottles made in the West Bank settlement of Mishor Adumim, was boarded up on Monday. This time last year, the management had reported a 40 per cent rise in sales.
Sussex Friends of Israel, whose supporters regularly staged counter-protests, reacted with dismay.
SFI co-founder Simon Cobbs said: "Of course it's disappointing. People are very upset. The shop was never given a chance of fair trade."
He accused Brighton Pavilion MP Caroline Lucas, a member of the Britain-Palestine All-Party Parliamentary Group, of not "doing anything to stop the protestors".
He said: "She wanted the shop shut by proxy, by not making the protestors move.
"EcoStream should have never opened in lefty-liberal Brighton in the first place, but it should have been given a chance."
A SodaStream UK spokeswoman confirmed that six people have been made redundant. She said: "Following a two-year test period, the company has decided to focus its business efforts on other channels.
"The business in the UK is on a high growth pattern, with over 20 per cent year-on-year growth and rolling out to new retail stores across the country."
Last week, John Lewis confirmed it would no longer stock SodaStream products due to "declining sales".
And this week SodaStream executives dismissed rumours that it would relocate to a new factory in the south of Israel.
In 2012 SodaStream received a NIS 25 million grant from the Investment Promotion Centre towards a NIS 130 million plant in the Idan Industrial Zone in the Negev.
But a SodaStream UK spokeswoman said: "There is no basis for these rumours. SodaStream has no further comment to add at this time."