Sir Peter Luff, a former Conservative party politician, took to Twitter with a photo of the display at Waitrose, captioning it with: 'Dear @waitrose, do you think your children's birthday cards may be just a bit stereotypical? #everydaysexism'.
The photo shows mostly pink cards for girls, with the words 'Birthday princess' and 'Special little girl' written on the front, while the boys' cards are mainly blue and read 'Birthday boy', with one showing a footballer and another an astronaut.
Sir Peter explained why he tweeted the photo, writing: 'Gender stereotyping does real harm to children and society by shaping and limiting ambition - pretty important.'
Quite a few of Sir Peter's Twitter followers were in agreement with him, 'Peter, I've a two year old girl who loves tractors, dolls & everything inbetween. You're [100%] right,' one person wrote.
'I'm father of 2 girls. Elder wants to be an engineer or archeologist, I encourage her to be who she is, not what society says,' another dad added.
Some, however, thought that his complaint wasn't important enough to warrant an actual issue with the supermarket.
''Real harm' are you for real? Asking young children what gender they want to be is far more harmful,' replied one woman.
'What is so wrong with gender targeted products?' asked someone else.
When Waitrose hadn't replied to his tweet, Sir Peter sent another to call the retailer out.
'Dear @waitrose, I'm a bit surprised by reaction but overwhelming majority seem to agree with me. If you've replied I've missed it – sorry,' he wrote.
Waitrose responded by replying to the tweet, writing: 'Hi Sir Peter, sorry looks like we missed this amongst the replies you received. We have a wide range of greeting cards which we are constantly reviewing to reflect what our customers want to buy.'
The store also told The Huffington Post UK: 'We have a wide range of cards which we are constantly updating to reflect what our customers want to buy and these already include many cards which are suitable for both boys and girls.
'We are working with our suppliers to explore how we can reflect a wider range of children's interests which aren't gender specific.'
Do you agree with Sir Peter? Let us know in the comments below!